shithub: plan9front

ref: d376fac66cbd5efbe2f9f61a1e8b31af03a84a92
dir: /sys/src/libstdio/tmpfile.c/

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 * pANS stdio -- tmpfile
 * Bug: contains a critical section.  Two executions by the same
 * user could interleave as follows, both yielding the same file:
 *	access fails
 *			access fails
 *	fopen succeeds
 *			fopen succeeds
 *	unlink succeeds
 *			unlink fails
 * As I read the pANS, this can't reasonably use tmpnam to generate
 * the name, so that code is duplicated.
#include "iolib.h"

static char tmpsmade[FOPEN_MAX][L_tmpnam+1];
static int ntmps = 0;

static void rmtmps(void);

FILE *tmpfile(void){
	FILE *f;
	static char name[]="/tmp/tf0000000000000";
	char *p;
	while(access(name, 0)==0){
		while(*p=='9') *p++='0';
		if(*p=='\0') return NULL;
	f=fopen(name, "wb+");
	if(f && ntmps<FOPEN_MAX){
		strcpy(tmpsmade[ntmps++], name);
	return f;

static void
	int i;
	for(i=0; i<ntmps; i++)